Re: [PATCH v4 01/11] drm/xe: Simplify module initialization code

[Rodrigo Vivi <rodrigo.vivi@intel.com>]

On Sun, Jul 27, 2025 at 07:19:58PM +0200, Michal Wajdeczko wrote:
> There is no need to have extra checks and WARN() in the helpers
> as instead of an index of the entry with function pointers, we
> can pass pointer to the entry which we prepare directly in the
> main loop, that is guaranteed to be valid.
> 
>   add/remove: 0/0 grow/shrink: 0/4 up/down: 0/-180 (-180)
>   Function                                     old     new   delta
>   xe_exit                                      109      79     -30
>   cleanup_module                               109      79     -30
>   xe_init                                      248     188     -60
>   init_module                                  248     188     -60
>   Total: Before=2774145, After=2773965, chg -0.01%
> 
> Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
> Cc: Lucas De Marchi <lucas.demarchi@intel.com>
> ---
>  drivers/gpu/drm/xe/xe_module.c | 27 ++++++++++-----------------
>  1 file changed, 10 insertions(+), 17 deletions(-)
> 
> diff --git a/drivers/gpu/drm/xe/xe_module.c b/drivers/gpu/drm/xe/xe_module.c
> index d9391bd08194..593bc9e5851a 100644
> --- a/drivers/gpu/drm/xe/xe_module.c
> +++ b/drivers/gpu/drm/xe/xe_module.c
> @@ -135,24 +135,17 @@ static const struct init_funcs init_funcs[] = {
>  	},
>  };
>  
> -static int __init xe_call_init_func(unsigned int i)
> +static int __init xe_call_init_func(const struct init_funcs *func)
>  {
> -	if (WARN_ON(i >= ARRAY_SIZE(init_funcs)))
> -		return 0;
> -	if (!init_funcs[i].init)
> -		return 0;
> -
> -	return init_funcs[i].init();
> +	if (func->init)
> +		return func->init();
> +	return 0;
>  }
>  
> -static void xe_call_exit_func(unsigned int i)
> +static void xe_call_exit_func(const struct init_funcs *func)
>  {
> -	if (WARN_ON(i >= ARRAY_SIZE(init_funcs)))
> -		return;
> -	if (!init_funcs[i].exit)
> -		return;
> -
> -	init_funcs[i].exit();
> +	if (func->exit)
> +		func->exit();
>  }
>  
>  static int __init xe_init(void)
> @@ -160,10 +153,10 @@ static int __init xe_init(void)
>  	int err, i;
>  
>  	for (i = 0; i < ARRAY_SIZE(init_funcs); i++) {
> -		err = xe_call_init_func(i);
> +		err = xe_call_init_func(&init_funcs[i]);

perhaps we can go further and avoid this extra function calling
directly here:

err = init_funcs[i].init();

>  		if (err) {
>  			while (i--)
> -				xe_call_exit_func(i);
> +				xe_call_exit_func(&init_funcs[i]);

and
init_funcs[i].exit();
here ?

>  			return err;
>  		}
>  	}
> @@ -176,7 +169,7 @@ static void __exit xe_exit(void)
>  	int i;
>  
>  	for (i = ARRAY_SIZE(init_funcs) - 1; i >= 0; i--)
> -		xe_call_exit_func(i);
> +		xe_call_exit_func(&init_funcs[i]);

and here
init_funcs[i].exit();

But either way is fine I guess...  up to you:

Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

>  }
>  
>  module_init(xe_init);
> -- 
> 2.47.1
>